Nissan Altima P0208: Injector Circuit Malfunction - Cylinder 8 diagnosis
Code verification standard
P0208 is published with SAE J2012 / ISO 15031-6 code structure plus Nissan Altima diagnostic context.
This page covers meaning, symptoms, first checks, live data, misdiagnosis risk, and repair verification.
What does this mean?
Code P0208 signifies a detected electrical fault within the fuel injector circuit specifically for cylinder #8. The Powertrain Control Module (PCM) monitors the voltage and resistance of the injector driver circuit. When the PCM detects an unexpected open circuit, short circuit, or out-of-range resistance in the injector's coil or wiring, it sets this diagnostic trouble code. This typically results in a misfire on cylinder 8, leading to rough idling, reduced engine performance, increased fuel consumption, and potentially a flashing Check Engine Light.
How serious is this code?
Driving with a P0208 code is generally not recommended for extended periods. While the vehicle may still be drivable, the misfire in cylinder 8 will lead to reduced engine power, rough operation, and significantly increased fuel consumption. More critically, an unburnt fuel mixture entering the exhaust system can rapidly overheat and severely damage the catalytic converter, a very expensive component to replace. It's best to diagnose and repair this issue promptly to prevent further damage and ensure safe vehicle operation.
Diagnostic system: General powertrain circuit
On a Nissan Altima, the P0208 code should be diagnosed as part of the general powertrain circuit group. Related codes and live data from this same system can change the repair priority, so avoid replacing parts from the code name alone.
Most Common Causes for Nissan Altima
- Clogged or faulty fuel injector
- Damaged, chafed, or broken wiring harness
- Corroded or loose electrical connector
- Internal PCM/ECM failure
- Faulty fuel pressure regulator
Symptoms to Watch For
- Check Engine Light is illuminated
- Engine misfiring or shaking sensation
- Rough or unstable idle
- Significant loss of engine power
- Poor acceleration or sluggish response
Before replacing parts, check these first
- Record freeze-frame data and related codes before clearing the fault.
- Inspect wiring, connectors, vacuum lines, fluid leaks, and fuses tied to the named system.
- Use live data or a multimeter to confirm the failed circuit before replacing parts.
- Check for blown fuses, weak battery voltage, and damaged connectors before buying major parts.
Live data to compare
- Freeze-frame conditions
- Related codes
- Circuit voltage and continuity
How to Diagnose
Common Mistakes
Treating the code description as a parts list instead of verifying the circuit, operating conditions, and related codes. Always confirm the fault with freeze-frame data, live data, visual inspection, and circuit checks before spending money on parts.
Repair verification
After the repair, clear P0208, complete a drive cycle, and confirm the monitor runs without the code returning. Save the before/after scan report if the vehicle needs emissions inspection.
Frequently Asked Questions
Can I drive with the P0208 code?
If the check engine light is solid, you can usually drive to a safe location or mechanic. If the light is flashing, pull over immediately to prevent catastrophic engine or catalytic converter damage.
Will the P0208 code clear itself?
Once the underlying problem is fixed, the engine computer will run its self-checks. If it passes over several drive cycles, the light will turn off automatically. You can also clear it immediately using an OBD2 scanner.
Will this code fail an emissions test?
Yes. If the Check Engine Light is on due to the P0208 code, your Nissan will automatically fail an OBD2 plug-in emissions or smog test.
What should I check first for P0208?
Record freeze-frame data and related codes before clearing the fault. Inspect wiring, connectors, vacuum lines, fluid leaks, and fuses tied to the named system. Use live data or a multimeter to confirm the failed circuit before replacing parts.
Join the Discussion
Repair Estimate
Fuse, connector, wiring, cleaning, or basic inspection
Major component replacement after live data and circuit tests confirm failure
Costs vary widely; start with visual inspection and circuit confirmation to avoid unnecessary parts.
DIY Difficulty
Can usually be performed at home with basic hand tools.